De Novo Urological Malignancies After Renal Transplantation: An Asian 30-Year Experience

BackgroundAs the incidence of urological malignancies after renal transplantation (RT) is observed to be greater than in the general population, a better understanding of them is important. We present our experience with urological tumors in RT recipients at our transplant center, and analyze their incidence, management and outcomes.Materials and MethodsA retrospective analysis of 2177 RT recipients on follow-up at our center between 1990 and 2022 was conducted for de novo genitourinary malignancy. Patients diagnosed with malignancy before transplantation were excluded. Clinicopathological data at diagnosis and follow-up were collected and analyzed. Kaplan-Meier estimates were used to evaluate overall survival (OS) and cancer-specific survival (CSS). Statistical analysis was performed using IBM SPSS v.24 (IBM Corp., Armonk, NY, USA).ResultsThe overall incidence of Urological malignancies was 3.9%, with 89 cancers diagnosed in 85 patients. Renal cell carcinoma was most common (n = 61, 68.5%), followed by prostate cancer (n = 10, 11.2%), urothelial carcinoma (n = 10, 11.2%), squamous cell carcinoma of the penis/scrotum (n = 7, 7.9%), and testicular cancer (n = 1, 1.1%). Mean duration between transplantation and diagnosis of malignancy was 9.9 (0.4-20.7) years. At a median follow-up of 4.6 (018.2) years, 27 deaths were seen; 7(25.9%) were due to urological malignancy. CSS rates were 86% and 78% at five and ten years, respectively, after diagnosis.ConclusionWe present one of the largest series of de novo urological malignancies observed over an extended 30-year follow-up of RT recipients, demonstrating an elevated risk in line with other studies. Regular surveillance for malignancies is advised, in order to ensure early diagnosis and management.